Portland cement compositions used as grouts and mortars generally contain a filler such as fine limestone or marble dust, a water soluble organic thickener for water retention, and until recently asbestos for sag control. The use of asbestos, however, has been severely curtailed or totally proscribed for safety reasons. A search for an asbestos substitute has yielded additives such as certain long-chain organic polymers, described in U.S. Pat. No. 4,021,257 and certain metal salts, described in U.S. Pat. No. 4,082,563.